{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2025-38082","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2025-04-16T04:51:23.981Z","datePublished":"2025-06-18T09:35:41.902Z","dateUpdated":"2026-08-05T11:59:20.241Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-08-05T11:59:20.241Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\ngpio: virtuser: fix potential out-of-bound write\n\nIf the caller wrote more characters, count is truncated to the max\navailable space in \"simple_write_to_buffer\". Check that the input\nsize does not exceed the buffer size. Write a zero termination\nafterwards."}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","baseScore":7.8,"baseSeverity":"HIGH"},"scenarios":[{"lang":"en","value":"AV:L - The bug is reached only via a `write(2)`/`pwrite(2)` syscall on the local debugfs files `/sys/kernel/debug/gpio-virtuser/<dev>/<line>/direction` and `.../consumer`. There is no network, remote-peer, or over-the-air input path into the gpio-virtuser driver.\nAC:L - A single unconditional write triggers it deterministically — a 32-byte write to `direction` guarantees an unterminated buffer and a one-byte OOB store past `buf[32]`, and a zero-length write to `consumer` guarantees `buf[strlen(buf)-1]` evaluates to `buf[-1]` on default `INIT_STACK_ALL_ZERO` kernels. There is no race, no timing window, and no memory-layout precondition outside the attacker's influence, since the attacker controls both the write length and every byte.\nPR:L - The debugfs nodes are mode 0644 and debugfs defaults to a 0700 root, but the `uid=`/`gid=`/`mode=` mount options and vendor chown policies commonly delegate debugfs to non-root system accounts on the embedded/industrial/automotive boards where a GPIO test-consumer device is instantiated, so a low-privileged local account is the realistic worst case — consistent with prior kernel CNA debugfs scoring (CVE-2025-38317, CVE-2025-38307).\nUI:N - The attacker performs the write entirely on their own; no victim action, mount, or file-open by another user is required.\nS:U - The corruption and disclosure occur in kernel stack/heap memory within the same kernel security authority, with no VM, IOMMU, or sandbox boundary crossed.\nC:H - `strim()` and `strlen()` read out of bounds past the stack buffer, and the unterminated buffer is handed to `gpiod_set_consumer_name()` → `desc_set_label()`, which `strcpy()`s the out-of-bounds stack bytes into a label exported to userspace through the debugfs `consumer` read and `GPIO_V2_GET_LINEINFO_IOCTL`; a `pwrite` at offset 31 leaks up to 31 bytes of uninitialized kernel stack, which can contain pointers and defeat KASLR.\nI:H - This is an out-of-bounds write — a NUL byte stored past the end of `buf[32]` in `direction`, and below the array (`buf[-1]`) or beyond it in `consumer` — at an offset the attacker can influence by grooming the kernel stack with prior syscalls, yielding a classic poison-NUL-byte primitive able to truncate an adjacent saved pointer or length field into a control-flow hijack.\nA:H - Corrupting adjacent stack locals, the stack-protector canary, or the frame of neighboring calls produces `__stack_chk_fail()` panics or oopses, and the OOB `strlen()` walk can fault; the attacker can repeat the write at will to guarantee a crash."}]}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/gpio/gpio-virtuser.c"],"versions":[{"version":"91581c4b3f29e2e22aeb1a62e842d529ca638b2d","lessThan":"afe090366f470f77e140ff3407db813f57852c04","status":"affected","versionType":"git"},{"version":"91581c4b3f29e2e22aeb1a62e842d529ca638b2d","lessThan":"b96feaaa0fda1e3871b438143c3446954b32d3a7","status":"affected","versionType":"git"},{"version":"91581c4b3f29e2e22aeb1a62e842d529ca638b2d","lessThan":"7118be7c6072f40391923543fdd1563b8d56377c","status":"affected","versionType":"git"}]},{"product":"Linux","vendor":"Linux","defaultStatus":"affected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/gpio/gpio-virtuser.c"],"versions":[{"version":"6.11","status":"affected"},{"version":"0","lessThan":"6.11","status":"unaffected","versionType":"semver"},{"version":"6.12.32","lessThanOrEqual":"6.12.*","status":"unaffected","versionType":"semver"},{"version":"6.14.10","lessThanOrEqual":"6.14.*","status":"unaffected","versionType":"semver"},{"version":"6.15","lessThanOrEqual":"*","status":"unaffected","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.11","versionEndExcluding":"6.12.32"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.11","versionEndExcluding":"6.14.10"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.11","versionEndExcluding":"6.15"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/afe090366f470f77e140ff3407db813f57852c04"},{"url":"https://git.kernel.org/stable/c/b96feaaa0fda1e3871b438143c3446954b32d3a7"},{"url":"https://git.kernel.org/stable/c/7118be7c6072f40391923543fdd1563b8d56377c"}],"title":"gpio: virtuser: fix potential out-of-bound write","x_generator":{"engine":"bippy-1.2.0"}}}}